OBJECTIVES:  Long-acting somatostatin receptor ligands (SRLs) approved as depot formulations are administered monthly, with an approved extension of a 6- 8 week subcutaneous injection interval possible for lanreotide (ATG120). Polish prospective non-interventional 2-years Lanro-Study showed that 48% patients received ATG120 mg at an extended duration interval. The aim of this study was to estimate the financial consequences of increasing the use of ATG120 in the treatment of acromegaly in Poland. METHODS:  An Excel-based budget impact model was developed to estimate the annual costs associated with treatment of acromegalic patients from the perspective of public payer in 2-years time horizon, using Polish epidemiologic and sales data, Lanro-Study results and drug acquisition costs. The following scenarios were compared: 1) current intervention mix (different dosage regimens of SRLs); 2) ATG120 is the 1-line medical treatment for all new patients; 3) all new and 50% of patients using so far octreotide LAR are treated with ATG120. in scenario 2) and 3) inadequately controlled patients were switched to octreotide after 6 months. Results were expressed in PLN (1 EURO=4.2 PLN in 2015). Scenario sensitivity analyses were performed RESULTS: In the scenario 1) the public payer expenditure on SRLs were estimated to be 47 997 242 PLN in 1^st